Enzyme engineering has the power to create several new discoveries and possibilities in the evolutionary field. Questions that were not answerable through decades of really hard biochemistry have now become accessible by integrating this evolutionary perspective. In the past, Rubisco faced many issues, such as starting to catalyze an undesired reaction, in which it mistakes O2 for CO2 and produces metabolites that are toxic to the cell. In the article by the Max Plank Society, researchers have discovered that the Rubiscos that show increased CO2 specificity recruited a novel protein component of unknown function, through resurrecting and studying billion-year-old enzymes in the lab using a combination of computational and synthetic techniques.

According to this article by Alejandra Manjarrez that analyzes that research, form I rubisco has the highest specificity for carbon dioxide and the most efficient catalytic activity. Form I Rubisco is made up of eight identical catalytic large subunits and eight identical small subunits. Researchers suspected that its enhanced ability to discriminate CO2 from chemically similar molecular oxygen could be related to the presence of these small subunits since no other forms of Rubisco have them.

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For years, research focused on changing amino acids in Rubisco itself, but new findings suggest that adding new protein components to the enzyme could be more productive. Rubisco is the most prevalent enzyme on the planet and is the key enzyme responsible for photosynthetic and chemoautotrophic carbon fixation and oxygen metabolism. It catalyzes the fixation of atmospheric CO2 to ribulose-1,5-bisphosphate (RuBP) to form two molecules of 3-phosphoglycerate (3PGA). This is the first part of the Calvin cycle which, as you learned in class, involves using atmospheric carbon dioxide, ATP, and NADPH to create G3P, which is the building block of glucose, through the processes of carbon fixation, reduction, and regeneration of the CO2 acceptor. With the new improvements in the efficiency of Rubisco and enzyme engineering as a whole, plants may be able to combat the increasing amount of carbon dioxide emissions hurting the earth through improved photosynthesis.